Investigations Experiments

Juan is interested in finding out whether hummingbirds are attracted to some flowers more than others. In what order should Juan perform the steps of his experiment?

1. Create a garden of different flowers.
2. Observe how many times hummingbirds visit each flower.
3. Write a report on his findings.
4. Record his observations.
5. Make a prediction about which flowers hummingbirds are most attracted to.

• 1 2 3 4 5

• 3 1 4 2 5

• 1 5 2 4 3

• 1 2 5 4 3

Assume that a recent study found that some chemicals in hot dogs caused clogged arteries in rats. In a newspaper article reporting the study, a consumer group concluded that people should eliminate hot dogs from their diet. Which of the following is an appropriate question to ask regarding this conclusion?

I. Do rats and humans react the same way to the chemicals?II. How much of the chemicals were the rats exposed to?

III. What type(s) of hot dogs were used in the study?

• I

• I & III

• II

• I, II, and III

Jordan observes that the roses in his garden seem to grow to different heights depending on their location in the garden. He does an experiment to test whether light availability affects the height that his rose bushes grow. He hypothesizes that rose bushes that receive the most direct sunlight will grow the tallest. The results from his experiment are shown below.

Rose Bush Hours of Direct Sunlight Average Height

Group A 0 hours 3 ft

Group B 4 hours 5 ft

Group C 8 hours 6 ft

Which is true about Jordan's results?

• Jordan's results do not support his hypothesis.

• Jordan's results are not related to his hypothesis.

• Jordan's results support his hypothesis.

• Jordan's results prove that all plants grow best in the Sun.

Jami is doing an experiment to find out how temperature slows down or speeds up the sprouting of bean seeds. To prepare for the experiment, she plans to put soil into three cups and place six seeds in each cup.

When Jami performs the experiment, which of the following is the only condition she should change for all of the cups of beans?

• the temperature

• the amount of water

• the amount of sunlight

• the amount of fertilizer

Raul wants to study how pot size affects the growth of plants. To do this, he intends to purchase three different pots of varying diameter. Then, he will fill each pot with the same amount of soil and plant different kinds of flowers in each pot. Finally, he will place the pots side by side in a sunny location and water each pot daily with the same amount of water.

Will Raul's experimental set-up produce valid results?

• No; Raul doesn't have a testable hypothesis so the experiment is pointless.

• Yes; Raul has a testable hypothesis so the experiment is valid.

• No; Raul changes more than one variable so the results will be invalid.

• Yes; Raul set up his experiment correctly so the results will be valid.

Your teacher has asked you to perform an experiment to see if the shape of objects, alone, affects the motion of objects. Which of the following would be the best experiment to perform?

• Apply the same amount of force to a ball, cylinder, cube, and pyramid, each of a different mass.

• Apply the same amount of force to balls of different masses.

• Apply different amounts of force to the same ball.

• Apply the same amount of force to a ball, cylinder, cube, and pyramid, each of the same mass.

Why is bias a problem in a scientific investigation?

• It will make the person doing the scientific investigation become ill.

• It may cause the person doing the investigation to get inaccurate results.

• It may cause the person doing the investigation to dislike doing it.

• It will make any chemical reactions stop before they are finished.

Corey's Science Experiment?

1.Purpose: To determine the effect that completely burning a log has on the weight of the log and to calculate the amount of energy transferred in the process.

2.Corey selects a log for the project.

3.He completely burns the log in a controlled environment.

4.He collects all of the ashes and soot which remain after the burning is complete.

5.He weighs all of the remains and calculates the amount of weight and energy transferred in the burning.

What is wrong with the steps of Cory's science experiment?

• He didn't measure the weight of the log before it was burned.

• He didn't set a time limit on how long he was going to let the log burn.

• He didn't have a partner there in order to verify the results.

• The log was going to completely burn; therefore, there wouldn't be any ashes left to measure.

Katie wants to do an experiment to test what factors affect the growth rate of sunflowers. She plants two groups of sunflower seeds in identical pots, gives them the same amount of fertilizer, and lets them sit in the sun for the same amount of time every day. She gives one group of seeds 10 mL of water a day. She gives the other group 1 mL of water a day. The group that receives 10 mL of water grows the fastest. Katie analyzes and publishes her results.

Based on the results of Katie's experiment, what question could she ask next to continue her research on sunflower growth rate?

• Will sunflowers grow to a larger maximum size in rocky mountain soil or in sandy soil from the beach?

• Will the growth rate of the sunflowers change if Katie increases the amount of water given to 20 mL a day?

• Will sunflower petals be a brighter yellow if Katie adds yellow dye into the water that she gives them every day?

• Will the growth rate of other flowers, such as roses, be affected by the amount of fertilizer given per day?

A scientist is observing a pack of wolves. She notices that whenever the pack wins a new territory, they bark and howl together for at least 15 minutes. The scientist forms the following hypothesis for the wolves' behavior:

Are wolves celebrating when they bark and howl after winning a new territory?

Why is this an invalid hypothesis?

• Barking and howling can only indicate hunger.

• Hypotheses should not be in question form.

• Wolves also bark and howl when strange animals enter their territory.

• Wolves bark and howl even when no new territory available.